SQL Server/T-SQL/Data Type/text

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READTEXT in a loop to read chunks of text.

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5> 6> CREATE TABLE myTable 7> ( 8> pub_id char(4) NOT NULL, 9> logo image NULL, 10> pr_info text NULL 11> ) 12> GO 7> SET TRANSACTION ISOLATION LEVEL REPEATABLE READ 8> SET TEXTSIZE 100 9> 10> BEGIN TRAN 11> 12> DECLARE @mytextptr varbinary(16), @totalsize int, 13> @lastread int, @readsize int 14> 15> SELECT 16> @mytextptr=TEXTPTR(pr_info), @totalsize=DATALENGTH(pr_info), 17> @lastread=0, 20> @readsize=CASE WHEN (@@TEXTSIZE < DATALENGTH(pr_info)) THEN 21> @@TEXTSIZE ELSE DATALENGTH(pr_info) END 22> FROM myTable WHERE pub_id="1622" 23> 24> IF @mytextptr IS NOT NULL AND @readsize > 0 25> WHILE (@lastread < @totalsize) 26> BEGIN 27> READTEXT myTable.pr_info @mytextptr @lastread @readsize 28> IF (@@error <> 0) 29> BREAK 31> SELECT @lastread=@lastread + @readsize 33> IF ((@readsize + @lastread) > @totalsize) 34> SELECT @readsize=@totalsize - @lastread 35> END 36> 37> COMMIT TRAN 38> GO 

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